Production of matrices or molds for printing-plates.



MICHAEL SMITH, OF PASSAIC,

.NEW JERSEY, ASSIGNOR TO THE RAPID ELECTRO- :nm ooMrANY, or CINCINNATI, OHIO, A CORPORATION or emo;

PRODUCTION OF MATRICES OR MOLDS FOB. PRINTING-PLATES.

Specification of Letters Patent.

Patented Apr. ta, 1914.

. Application filed February 20, 1913. Serial mo. ?49,641.

Ta all whom it may concern Be it known that I, MICHAEL SMrrH, a citizen of the United States, residing in the city and County of Passaic and State of New Jersey, have invented Improvements n the Production of Matrices or Molds for Printing-Plates; and in order that others sklled in the art may understand,tmake, :and use my invention I give the following description. 4

My invention-relates to the production of printing plates, stereotypes and the lke and has for its object the production of matrces or molds in which such printing plates, stereotypes and the like may berapidly and inexpensively produced and which wll produce stereotypes or'printng plates of* great perfection of the design or type characters and of great accuracy as to dimensione.

I have illustrated my invention and the mode of carrying out the same in the accompanying drawings, in` which, i

Figure 1 is a plan' View of a-frame for holding 'the set-up type or other matter from which a matrix is to be made; Fig. '2 is a cross sectional view taken on the line X-X, Fig. 1; Fig. 3 is a plan view of a frame or mold for production of a printng plate -or stereotype; Fig. 4 is a cross seotonal V ew taken on 'the line Y--Y, Fg. 3; Fg. 5 s a broken View illustrating a matrix, and Fg. 6 i a similar View showing a printing plate.

Similar reference numerals are ap'pled to corresponding parts in the several views;

In carrying out my`invention I take a form of set-up types, or a block or plate of typographic matter, oi' an engrayed metal or half-tone plate hearing a desgn on ts face and secure the same within a frame 1,

as shown in Fig. 1. Such'frame may be an ordinary printer s Chase. For convenience of illustration I have shown a form 2 of set-up type matter Secured in said fram'e 1', but it will be understood that where the design to be rep'roduced is on a relative! thin body such' as an engraved metal or hal- -tone plate,

` such plate will be suitably backed up 'in order to bring its face to ri ht height with respeet'to the frame 1, for orming. the matrx there n As great acuray of s ze s requ te n stereotypes nd p r rting PM Order hol or other solvent.

they will fit into place when setting up the press, I provide for obtaining this accuracy n the size of the matrix by securing metal strps 3 around the sides of the form 2 when nserted in the frame 1. These metal strips 3 should be Secured firmly and close up against the sides of the form 2 so as to accurately define the same. These metal strips 3, as shown in Fig. 2, about the sides of the form that their upper edges come even or flush with the type faces or face of the design. The upper edges of said strps 3 are beveled outwardly, as shown at 4, so as to form sharp mar-king or cuttng edges of the matrix, which edges oomcde with the sides of the form 2 and thus accurately determine the size of the matrix, as will hereinafter more fullyv apshould be so Secured by the screws 5, or other clamping means,

by which the form 2 is locked in the frame l; or said strips may be Secured directly to the sides of the form by any suitable fastenlng means.

For forming the body of the matrix I em- `ploy a sheet of fibrous compressible material' in which the fibers are more or less loosely felted together and saturate said material thoroughly with a solution of a gum 'or resin, such, for example, as shellac, gum copal or resin dissolved in wood alco- For the fibrous compressible material I have found the material known as straw board, and largely used for making paper boxes, when saturated and impregnated with the gum or resin, possesses the property of taking and retaining perfect impressions of typographic and similar designs used in printing. For` finer or more delicate and detailed designs I pre- `fer .to face one side of said fibrous compressible material by afiixing thereto a sheet of blotting paper of about one thirty-second of an inch "in thickness, .said blotting paper sheet being also saturated with the gum solution. Or 'the matrix material may be wholly of the blotting paper of a thickness of about one-eighth of an inch, though this 10O will increase the cost. nearly three times. When theblotting paper facing is used, as above described, 'the straw-board sheet to which it -is axed-'will be about three-sixteenths ofaninch in thiclmes s. -Sheets of the character described having been thor- T oughly saturated and impregnated with, ,gunt or resin soluton are to evaporate the solvent. This treat-ment makes the sheets quite hard and stiff; but when' said sheets are brought under the influence of heat up to about 250 F. they become quite soft and pliable, resuming their hardness and rigidity on cooling.

To form a matrix, a sheet or portion of.

the described material, about one-half of an inch larger all around than the form or plate 2 to be reproduced, is taken and heated thoroughly mtil it is quitesoft and pliable. The form 'or plate 2 with the strips 3 having been previously locked up 'in the frame or chase 1 is thinly and uniformly coated with a film of glycerin, care being taken to have. such coating uniform .and thin, 'so as not to mask any of the 'fine lines or details of the design. 'The heated'and softand pliable sheet is then laid on the form or plate so prepared and firmly and evenly pressed thereon, with a pressure ofabout fifty pounds to the square inch; though a heavier pressure may be employed if ,desired. Such pressure may be performed in' any good and accurate press. The operation of taking the impression should be performed quickly,

and all the appliances.` required therefor' should be ready, as the heated, plastic 'sheet cools quickly,'and if permitted to cool appreciably it correspondingly hardens and the impressions taken may then lack depth and sharpness. By proceeding as described the sofe and pliable sheet is forced into the finest details of the design and a matrix is produced which is a perfect reproduction of the design, with all 'the details clear and sharp, and of a depth up to the shoulders of the type with a deeper surplus for the empty spaces. When cool and hard the matrix is separated from the form or plate,

- 7 the. facing -of blottmg paper.

- From a matrix produced as described a number of positive printing plates may b'e produced, articularly if made of the material heremafte-.specified. For'formin'g a prntng plate or stereotype from said matrix the latter, accurtely 'sized as described,

exposed to drying is suitably blocked up by placin .the same upon' a block's, Fig. 3, with the esign face presented upwardly; 'Around the' block 8 and close up against the edges of the same and of the matrix are Secured brass strips 9. These strips 9 are beveled at their upper edges as at 10, to form sharp edg'es, the bevel being i'nelined out-wardly, as shown. The height of the strips 9 determines the thickness of the stereotype' or printing plate. to be formed. For example, if such plate is to he threesixteenths of an inch thick said strips must extend three-sixteenths of an 'inch higher than the face impressionof the type in the matrix. If ste'reotypes or plates of greater thickness 'are desired said strips will be correspondingly higher. A The backed up matrix with the strips 9 closely and firmly .Secured about the edges of the same 'is locked up in a frame or'chase 1, by means 'of the screws' 5 or other looking' means; said screws or looking means may also serve as the means for holding strips 9 closely and securely about the edgesofthe matrix and block. When so arranged the matrix and strips 9 form a mold in which the material for' forming the 'stereotype or printing plate may be pressed. v

Any suitable stereotype material may be employed, but Lprefer to employ one that is hard or semi-hard at normal temperatures and is rendered soft and plastic by heat at a temperature less than that which softens the matrix material. For such material I preferably employ that described in the application of Eugene C. Smith, Serial No. 746242 filed February 4:th, 1913. This material can be obtained in sheets of even, straight and smooth surface and uniform in thickness throughout. As stereotypes and printing'plates should be of *uniform thickness for good printing, this is a feature of advantage. Said material while hard or semi-hard at normal temperatures becomes soft and plastic at about 200 F. in which condition it takes perfect impressions such. 'as are required in printing plates, and does not contract on cooling' As such sheets would in their heated and soft condition be difficult to handle and apply to the matrix, I first unite such sheets to a hacking of stifl' paper, or of wood, by means of a cement,

such as shellac or celluloid cement orthin glue. Large sheets of the material, backed as, described, may be prepared (say 241130 inches in size) and kept on hand and piecesof the sizes required for printing plates may be cut therefrom'from time to tme'as'needed. As great accuracy and uniformity of thickness of stereotypes and printing plates is required, the thickness of the material on quired for the finished plate, to allow for the pressure exerted thereon' in making the the hacking should be greater than that repr m A D e e sa d ba sl "ieeteral of a size sonewhat larger than that required for the' plate or stereotype is taken and' coated wit a" of the finest plum bago by means .of a brush or pad, and a film of the same materialji also applied to the matrix, care being taken thatall loose plumbago particles are removedthe object being out around the coating of plumbago to insre clean' S' p-I.-

tion of the' surfaces after impression;

The matrix having been prepared as described and locked in frame 1, the backed sheet is placed on steam table or otherwise' uniformly heated to a temperature of about 200 F. or until it is converted into a soft and plastic condition. In this condition it is laid on the matrix in said frame and the whole placed in a strong and accurately opy erating press and subjected to pressure to force said mater al sign on the matrix.

the required into the de- The pressure will force 9 the surplus material, the escape of which will cease as soon as the hacking comes into hard contact with the edge's of the strips 9. The pressure is maintained until the matev rial has cooled when it 1S removed from the .holdin press and lifted from the matrix. After trimming oli the hacking the stereotype or plate is ready for use. Fig. 6 illustrates such plate in which 12 is'the material in which the design is impressed and 11 is the hacking. The stereotype or plate so produced is accurate as to form, dimensione and thickness, is' flat and smooth on 'the 'back and has its edges formed with an angle or bevel corresponding to the bevel of the strips 9, which bevel is required when the plates' 'my invention provdes means by which matrces may be for-med readily and inexpensively; that said matrices reproduce with sharpness, depth and great perfection the design in all its fine details, and maybe repeatedly used to formistereotypes and 'printing plates, and that the plates or stereotypes produced therefrom are accurate as to size, back and thickness and ready for use on the press without further Operations.

What I claim is: 1. A matrix material for forming stereotypes and printing plates, said material consisting of a fibrous compressible material,

' plasti edges formed by the strips' y a g p ates, a d m er a o i sst ng of strawboard impregnated with a '1' at` nrmal temperatiires and 'o t aha c and capable of taking fine designs by impression when heated to a temperature of about 250 F.

3. A matrix material for forming stereotypes and printing plates, said material consisting of a body portion of fibrous compressible material, a facing of blotting paper on said material, said facing and body portion impregnated with a gum or resin, said matrix material being hard and rigid at normal temperatures and soft and plastic and a resi s id ..material and capable of taking fine designs by. impression when beat/ed to a temperature of about 250 F. I

4. A matrix material for forming stereotypes and printing plates, said material conssting of a body portion of strawboard, a facin of blotting paper on said vstrawboard, said ody portion and facing impregnated with a gum or resin, said matrix material being hard and rigid at normal temperatures and soft and plastic and capable of taking fine designs by impression when' heated to a temperature of about 250 F.

5. The process of forming matrices for stereotypes and printing plates which consists in saturating a fibrous compressible material with a solution of a um or resin in a Volatile solvent, evaporatng said solvent, heating the material so treated to make the same plastic, ,pressing the same on the form or design to be reproduced, and maint aining said pressure until the material is cool, then separating the material from the form or design. 4

6. The process of forming matrices for stereotypes and printing plates which cong sists in saturatmg a fibrous compressible material with a solution of a gum or resin in a volat ile solvent, similarly saturating a facing sheet of blotting paper superposing said facing sheet on the fibrous compressible material drying said sheets to evaporate the solvent, heating said sheets to render the same soft and plastio, pressing the same on the form or design to be reproduced with the facing in contact with said design, maintaining said pressureuntil the material is cool and separating the inaterialfrom the design.

7. The process of forming matrices for stereoty'pes and printing plates which consists in saturating a fibrous compressible material with a solution of a gum or resin in a volatile solvent, evaporati'g said solvent, coating the form or design to be re produced wth a film of glycerin, heating 4 the material sotreated to make the same 6 plastic, pressing the same on the form or design to be reproduced, and maintaing 'said pressure until the material is 0001,' then separating the material'fr'm the form or design. 4 MICHAEL SMITH; witnesses:

JOHN J. C. SMITH, t

' ROBERT OFFonp. 

